These are my first finches. I got them after they were pushed from the nest and abandoned by their parents when they were about 2-3 weeks from a work aviary. I have been hand-feeding them for 2.5 weeks now. They appear to be thriving.
My questions are:
1) I still have a lamp in the cage with them, when is it okay to remove the light? Also what temperature should they be in if they are 4-5 weeks?
2) I have them housed in my old cockatiel cage with finch-appropriate perches. They seem to prefer sitting in the dishes when they sleep, but refuse to sleep in the toweled-bowl at the bottom of the cage. Would one of those hanging nests be better for them? Or something else I haven't thought of?
Any other advise would be appreciated as well!

Thank you!